This invention relates to an improved venturi based vacuum valve for modifying the flow rate of liquids. More particularly, this invention relates to a venturi based vacuum valve for improving flow pressure at a lower flow rate.
No one debates the need for water conservation. Low flow water devices have been introduced to conserve both toilet and shower water use. Some low flow shower devices are as simple as placing flow restrictors anywhere along the main water stream so as to interrupt the flow of the water. A problem with these low flow shower water devices in the prior art, however, is that while water flow rate is reduced, the water flow is also reduced so that the feel of a shower at high flow rates is lost altogether. Recently, prior art devices have been developed that introduce air into the water stream at the shower nozzle. This inventor is aware of a product marketed by the DuPont Company under the trademark SPA2001. This device is a shower nozzle with a variety of moving parts that is designed to suck air in at the outlet end of the shower nozzle and introduce it upstream of the outlet.
Drawbacks to the devices known in the art, and this particular DuPont device, are that they require the elimination of the pre-existing shower head with which the user has become accustomed, they include a variety of moveable parts and attachments, and they introduce air from the outlet thereby increasing chances of clogging and fouling with water expelled from the outlet end of the device. Thus, there is a need in the art for providing an improved venturi based vacuum valve that includes no moving parts, that enables the use of existing shower heads, and which provides a venturi effect away from the outlet end of the shower head. It, therefore, is an object of this invention to provide an improved venturi based vacuum valve which includes no moving parts, which is compatible for use with existing shower heads, and which has a venturi effect opening at a location removed from the outlet of the valve.